1. Field of the Invention
The present invention relates to a gas control module switch mechanism and particularly a switch mechanism for accurately controlling open and stop of gas flow in a piping system.
2. Description of the Prior Art
Conventional techniques for gas control module switch mechanism generally use metallic diaphragm for sealing gas. However metallic material usually has relative hard property and is difficult to get precise sealing effect desired and may result in gas leaking. In semiconductor industry, a great number of control valves have to be deployed for precisely control gas flow. The gas is usually highly toxic. It is essential and critical to prevent gas leakage. On the other hand, metallic material is easy to wear off and has relatively short useful life span, and often results in increased frequency of repairs and maintenance, and higher maintenance cost.
FIG. 1 shows a conventional technique. There is a valve body A5 which has a gas inlet A3 and a gas outlet A4. The gas inlet A3 is engaged with and surrounded by a replaceable valve seat A1 which includes a round sealing barrel A11 and a seal member A13. The sealing barrel A11 and seal member A13 are both machining parts. After using for a period of time, the seal member A13 and a metal seal A2 will be worn off because of constant friction between each other and need replacement. For replacing the valve seat A1 and metal seal A2, the valve body A5, cylinder A6 and brake linkage bar A7 should be disassembled. It is very time consuming and further increases maintenance cost. As a result, this technique has the disadvantages of poorer sealing effect, increased cost in consumption materials and maintenance, and more production time loss.
The main problem of the conventional structure mentioned above results from complicated design. If the disassembly of the structure were limited to only the valve body A5, or cylinder A6 and brake linkage bar A7, replacement of parts related to sealing may all be done at one time. Maintenance cost may be greatly reduced. The whole structure will also be simplified and may result in lower production and machining costs.
The present invention aims at using relative soft material and improved structure to resolve the problems incurred to conventional techniques for achieving the following objects:
1. to increase useful life of consumption materials and reduce maintenance frequency,
2. to simplify design and lower production cost,
3. to make machining easier and reduce machining defects,
4. to make assembly work simpler and make maintenance faster at a lower cost.